SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a599f524c3c39230960520407792038db52378a73f584c2961a42e628f716c66' 
  AND token = 'rkh7j8LUichJA1GRvYpva5D7M9nV03KZHaTqIG7KHCM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}